Coronary heart disease (CHD) is still the most prevalent cause of death in the US. Despite its multifactorial etiology, plasma cholesterol levels are considered to be a useful predictor of risk and numerous interventions are continuously tested in a effort to control hypercholesterolimia. Research has suggested that insulin resistance may play a central role in the pathophysiology of CHD. Thus, there has been an increasing interest in insulin and glucose metabolism as relevent parameters in disease intervention or prevention efforts. A large body of evidence supports a role of soluble fiber in both reducing serum cholesterol concentration and improving fasting and postpandrial blood glucose and insulin levels. The mechanism by which fibers exert these effects is largely unknown, but it is thought to be at least partially related to its viscous nature. The purpose of this six-week, double-blind, placebo-controlled study is to investigate the cholesterol-lowering effect of modified cellulose as well as its ability to beneficially modulate glucose and insulin metabolism. The unique physical characteristics of this fiber contribute to contribute to its high water-holding capacity, yet it is virtually non-fermentable. Thirty men and women, randomized to an active or control treatment group, will be asekd to consume 8 fl oz of beverages differing in fiber content twice daily for six weeks. Bllod samples will be drawn pre- and post-intervention to measure serum levels of fasting lipids, insulin, and glucose. Additionally, the participants will undergo an meal challenge and an intravenous glucose tolerance test to determine cholecystokinin, glucose and insulin responses. The data will be analyzed for differentces between pre- and post-intervention values for all parameters studied.